Tone arm trip mechanism for phonographs



Jan. 13,1942. T. MWRIGHT 2,270,179

' TONE ARM TRIP MECHANISM FOR PHONOGRAPHS F'iied March 17, 1959 2 Sheets-Sheet 1 Patented a... 13, 1942 Fries- 'roNE Ann 'rnm nmcnamsn FOR rnonoonarns Theodore M. I

assignor Wright, North Tonawanda, N. Y., to The Rudolph Wurlitzer Company, North Tonawanda, N. Y.,

a corporation of Ohio Application March 17, 1939. Serial No. 262,463

6 Claims. (01.274-1) This invention relates to certain new and useful improvements in tone arm trip mechanisms for phonographs for automatically control ling the restoration of, the tone arm and the actuation of other parts of the instrument to initial or starting position at the completion of playing a record.

It has for one of its objects to provide a trip mechanism of this character which is so designed as to be effectually actuated upon an abnormal inward swing of the tone arm, as when its stylus encounters the terminal'groove of the record or even a record which has no such groove.

Another object of the invention is to provide a simple, reliable and positive tone arm trip mechanism which is operatively'associated with v A, and governed from the turntable-axis and tone armaxis to normally effect an idling or noneifective action of such mechanism, as during the-playing of a record, and to automatically impart an effective tripping stroke thereto at the end of the playing of the record.

Other features of the invention reside in the construction and arrangement of parts hereinafter described and particularly pointed out in an automatic phonograph showing my improved trip mechanism associated therewith. Figure 2 is a top plan view, partly in section, of the trip 7 mechanism, the same being shown in its idling or non-tripping position. Figure 3 is a cross-section taken on line H, Figure 2. Figure 4 is a fragmentary perspective view showing the trip mechanism in tripping position. Figure 5 is a frag mentary plan view of the trip-governing elements and associated parts, showing the position of the trip pawl in its instroke. position, preparatory to I being displaced to a tripping position. Figure '6 is a fragmentary horizontal section taken on line 5-8, Fi e 1.

dimilar characters of reference indicate corresponding parts throughout the several views.

By way of example, my tone arm trip mechanisin has been shown in connection with an automatic selective phonograph of the type shown in the Wilcox Patent No. 2,002,236. dated May 21, 1935, 10 indicating the platform or supporting frame of the phonograph chassis, H the turntable, t2 the tone arm 'or reproducer mounted on an upright post it for'iateral swinging movement over the selected record. Each record It may be carried in a horizontally-swinging tray 15 which is adapted to be selectively swung from coupling engagement with one or anotherof the record trays to selectively swing it from the, carrier stack to a position over the turntable and this swinging of the yoke is efiected through the medium of a vertically-swinging lever l'l operated by a cam l8'fixed on a driven cam or operating shaft. l9 and connected at its upper end by'a link 20 with such yoke. the rotation of the cam shaft, the clutch bein released during the playing of a record and being engaged to rotate the cam shaft and restore the record-changing mechanism including the carriers [5 as well as the tone .arm to its initial position. A clutch-actuating lever 22 isfixed on an oscillatory shaft 23 having a radial rod-24 projecting therefrom in operative relation with a lug 25 formed on an actuating arm 26 pivoted to such shaft and having a spring 2'! applied thereto. for urging'it in a direction to bring its' to the shaft I9. In the playing position of the phonograph, the cam-pin 30 holds-the latching arm 26 in a position to place the spring 21 under tension, so that when a record has completed its play and the tone arm trip mechanism is rendered operative to release it from latched engagement with the armeproiection 26 the spring will thereupon actuatethe latching arm in a direction to rock the shaft 23 and shift the clutchactuating lever 22 to a position to effect the auto-' matic engagement of the clutch 2| and thereupon render the record-changingmechanism operative to-restore the played record to the stack and return the tone arm to its initial position.

- The return, of the tone and to its initial position may be eifected simultaneously with the swinging of the cari'ierback to the stack by the lever l1 and for this purpose the latter has a projection 32 arranged to'engage an arm 33 applied to the lower end of the tone arm post 13.

As shown in Figure 2, the turntable-spindle 3% may be driven by a worm and .worm wheel 3% and 38, respectively, the worm being driven from A suitable clutch 2! controls" an electric motor or other source of power. Likewise, the clutch-controlled operating shaft l9 may be driven by a similar worm meshing with a worm wheel i9"- having an annular row of notches iii in one face thereof with one or another of which a pin 2| on the shiftable sleeve 22- of the clutch 2! is adapted to engage. A spring 2| normally urges the sleeve in a direction to bring its pin into engagement with a companion notch in the worm wheel IS.

The improved tone arm trip mechanism is so designed that it is operatively associated with and governed by the combined movements of the tone arm and turntable-spindle about their respec tive axes, so that during the normal playing of the record the tone arm moves uniformly inwardly and the movement of the turntablespindle merely imparts an idling motion to the trip mechanism without effectually actuating it to a trip position. However, whenever the abnormal inward swing is imparted to the tone arm, as when the playing of the record is completed, an effective stroke is imparted to the trip mechanism to actuate it to a trip position and shift the clutch to its operative or engaged position to render the record-changing mechanism operative and to restore the tone arm to its initial position. In the preferred embodiment of this trip mechanism shown in the drawings, it is constructed as follows:-

The numerals 38 and 39 indicate parallel superposed trip-governing elements which are mounted for relative linear and lateral movement in a substantially horizontal plane, the lower element 38 having a friction pivot connection 40 with a bracket plate 4| applied to a post 42 depending from the platform Ill adjacent the turntable-spindle 34. As shown in Figures 1 and 2, these elements are disposed generally radially relatively to the spindle-axis and in opposing endwise relation to the pivoted tappet 28. The upper trip-governing element 39 is pivotally connected at its inner end to a, horizontally-swinging arm 43 pivoted to the post 42 and having a spring 44 engaging the same for constantly urging said arm to rock ina direction toward the turntable-spindle. Mounted on the latter is a cam 45 with which the arm 43 engages so that during the rotation of the spindle the rock arm is intermittently rocked in and out and the attached trip-governing element 39 is reciprocated in a like direction relative to the companion trip element 38, both trip elements, however, being caused to jointly swing laterally about their respective pivots, in response to the tone arm movements as hereinafter described. Relative lateral displacement of the trip elements 39, 39 is limited in each direction by pins 46 rising from opposite sides of the lower element 39 for edgewise engagement with the upper trip element. At its outer free end the lower trip element terminates in an upstanding lug or shoulder 41 which is provided at one edge with an inwardly-facing tooth-like projection 49, while the companion upper trip element 39,,which is somewhat shorter than the lower trip element, terminates at its garter free end in an upstanding lug or shoulder Pivotally mounted on and adjacent the outer end of the upper trip-governing element 39 for pivotal and longitudinal movement relative thereto is a tripping pawl 50 for actuating the tappet 28 to clutch-releasing position and connected through a longitudinal slot 5| with a pivot screw 52 borne by the upper trip-governing element. The outer or free end of this pawl has an extension 59 resulting in an outwardly-facing shoulder 54 which is disposed in alinement with the lug 49 of such element to abut against the same in the tripped position of the pawl, as shown in Figure 4. Formed at the outer end of this pawl-extension 53 is a substantially V-shaped notch or throat 55, which is adapted to move into and out of register with the tooth-like projection 49 on the lug 41 during the reciprocating movements of the trip-goveming element 39. A spring 55 connected to this pawl and the lug 49 of the upper tripoverning element serves two functions, firstly, to normally urge the pawl longitudinally outwardly with its notched end in cooperating relation with the tooth-like projection 49, and, secondly, to laterally swing the pawl about its pivot 52 so that the inner edge of its extension 53 bears against the opposing edge of the lug 49, as shown in Figures 1 and 2. During the playing of the record the spindle-cam reciprocates the upper trip-governing element 39, and during this period the pawl is maintained in substantially alining relation thereto with the spring 59 urging. the pawl in a direction to bring its V-shaped throat into registering engagement with the lug-tooth 48. The relationship of the pawl-pivot 52 and its mating slot 5| is such that during the in-stroke movement of the reciprocating element 39, the pivot abuts the inner end of the slot and shifts the pawl lengthwise therewith to free the notched end thereof from the tooth 48, as shown in Figure 5. During the out-stroke movement, the pawl is freed from abutting engagement with its pivot and is urged by the spring 59 into engage-v ment with said tooth, as shown in Figure 2. This movement of the parts initiated by the spindle-cam is merely an idling one and there is no lateral displacement of. the tripping pawl effected until an abnormal movement of the tone arm takes place, as when entering the extension groove in the record, at which time an abnormal lateral displacement of the upper trip-governing element 39 together with the tripping pawl 59 is effected to bring the parts to a trip-operating position.

The lateral displacement of the trip-governing element 39 and its associated pawl 50 is preferably initiated from a connection between the tone arm post 13 and such trip-governing element. As shown in Figures 1 and 2, this connection consists of an arm 59 radiating from the lower end of the tone arm post l3 to turn therewith and connected by a link 59 to one arm of a horizontally swinging lever pivoted intermediate its ends at SI and having its other arm connected by a link 52 with the upper pawl-governing element 99. By this construction, during the uniform inward swing of the tone arm, as while playing the record, this lever and linkage connection imparts a gradual laterally-swinging movement tothe upper element 39 and due to the operativerelation between the pawl 59 and the lower trip-governing element 39, the latter is simultaneously displaced with the companion element 39. However, in response to a smart'inward swing of the tone arm beyond that eflected by that of the playing grooves of the record, the lever and linkage connection abnormally displaces the trip-goveming element 99 to swing it and the pawl 59 to a position wherein the notched end of the pawl is disengaged from and out of register with its latching tooth 49 and the spring 59 immediately acts to project the pawl outward to 'atripping position, as shown in Figure 4. In this connection the tappet 28 has a flange 63 thereon disposed in the projecting path of travel rock the clutch-governing lever 22 from itsclutch-releasing position to the position for enabling the clutch to be automatically urged to its engaged position. I Y

At a. predetermined time in the record-changing cycle, the lever 22 swings down by gravity into engagement with the cam surface of the shiftable clutch element, shown in Figure 2, to eii'ect the release oi'the clutch and at the same time rock the shaft 23 in a direction to swing the arm 26 to its initial position to bring its projec- HD5235 into latched engagement with the tappe A spring 65 coiled about the pivot 64 and engagingthe underside of the tappet 28 normally urges the latter to its latching position shown in Figure 1.

I claim as my invention:

1. A trip mechanism for the tone arm of a phonograph, comprising a latch member for releasabiy latching an actuatable part of the phonograph in a normal position, a pair of superposed trip-governing elements generally radiating from the turntable spindle toward said latch member and pivoted for laterally swinging movement, one of said elements being displaceable longitudinally relative to the companion element, means adapted for rotation with the turntablespindle and operatively engageable with said longitudinall'y-displaceable element for imparting idling reciprocating movements thereto, a trip device mounted on saidlongitudinally-dis placeable element for movement relative thereto and projectable at a predetermined time into tripping engagement with the latch member, a

spring connectedto said trip device for normally maintaining it' in a non-tripping position and at another time urgingit to a trip-seeking position, and means adapted for connection at one end to the tone arm and at its other end to said trip member mounted on one of said relatively movable elements for movement into and out of releasable engagement with the companion element and ioreindependent movement when released" into tripping engagement with said latch member, a spring applied to said trip member for urging it to a trip-seeking position, means adapted for rotation with the turntable-spindle for imparting uniform relative movements to said trip-governing elements, and means adapted for connection to the tone arm for initiating the movement of the trip member to a trip-seeking position at a predetermined time in the relative movements of the trip-governing elements and upon an abnormal inward-swinging movement of the tone arm.

4. A trip mechanism for the tone arm of a phonograph, comprising a latch member for releasably latching an actuatable part of the phonograph in a normal position, a releasable trip device engageable with said latch member for shifting it to a released position, spring means associated with said trip device for urging it to, a tripping position when the same is released,

meansoperatively engageable with the trip device ior normally preventing its movement to a released tripping position, and

means adapted for connection swinging the latter and the trip device to a released tripping position upon an abnormal inswinging movement of the tone arm.

5. A trip mechanism for the tone arm of a phonograph, comprising a latch member-for retrip device for moving the latter to a displaced position wherein said spring acts to urge the trip device to a tripping position upon an abnormal inward-swinging movement of the tone arm.

and laterally movable trip member disposed in operative relation with said latch member for shifting it to a released position, means including a rock arm and cam operatively connecting said trip member with said turntable-spindle for imparting a constant linear movement to such member to and from -'a given position, and an operative trip-initiating connection between the tone arm and said trip member for laterally displacing the latter upon anabnormal inwardswinging movement of the tone arm and at a predetermined time in the linear movement of such member.

3. A trip mechanismifor the tone arm of a phonograph, comprising a latch member for releasably latching an actuatable part of the phonograph in a normal position, relatively movable trip-governing elements disposed between ,joint lateral-swinging movement,

leasably latching an actuatable part of the pho-.

nograph in a normal position, relatively movable trip-governing elements disposed between the turntable-spindle and the elements being pivoted adjacent said spindle for means adapted for connection to said spindle and operatively trip-governing elements it periodically toward and from said latch member, a pivoted trip member mounted on said reciprocating element for movement therewith in one direction to'and from coupling engagement with the companion tripgoverning element, a spring connected to said trip member for yieldingly urging it in the opposite direction to a trip-seeking position, and. an operative connection between the tonearm and said reciprocating, trip-governing element for laterally swinging the latter gradually during the normal inward swing of the former, said conection, during an abnormal inward swing of such arm, causing a smart lateral displacement of the reciprocating trip-governing element and the trip member from coupling engagement with the companion trip element and causing said spring to urge, said trip engagement with said latch member.

6. A trip mechanism for the tone arm of a phonograph, comprising a latch member for releasably latching an actuatable part of the phonograph in a normal'position, relatively movable trip-governing elements disposed between the turntable-spindle and the latch member, said the turn a p nd the latch member. a elements being pivotedadjacent said spindle for combined reciprocating and laterally-swinging trip-governing movement to said tfl-P-BOV- and at its other latch member, said member into tripping I joint lateral-swinging movement and each having a stop shoulder adjacent the free end thereof, means adapted for connection to said spindle to turn therewith and operatively connected to one of the trip-governing elements for reciprocating it periodically toward and from said latch member, a trip member having a pivotal, sliding connection to said reciprocating element and having shoulders thereon complementary to said first-named shoulders, a spring con mated to said trip member for yieldingly urging it normally to a position to bring its shoulders into contacting engagement with the companion shoulders of THEODORE M. WRIGHT. 

